AWiFs Collection, Norman, OK

Toney Cooper

ASRC Ground Station

Brief History

• Operations began in April of 1992

• First commercial ground station that supported LandSat4, 5, & 6

• Continue to provide operational support for Resourcesat-1, Ikonos, and IRS-1D

• Added IRS Production capabilities in 1997

Overview

• Process Flow of Norman Operations

– Data Acquisition

– Data Capture

– Data Processing

– Orthorectification of Resourcesat Imagery

– Final QC

– Product Delivery

• Q&A

Data Acquisition

•The Norman Facility includes

–Datron 11 meterparabolic dual S-band/X-band Antenna

–Steerable ViaSat(Scientific Atlanta)Antenna

–Grounded lightning rods

–Configured forredundancy and multi-mission supports.

Data Acquisition

•Customer specifies path, row,quad, and date for collection

•Inside CONUS:

–Scenes down linked andcaptured in real-time toNorman Operations facility.

–Norman Operations supports2-3 Resourcesat acquisitionsper day during growing season.

IRS-P6 Receiving Stations

Norman, Oklahoma: GeoEye

Fairbanks, Alaska: Geoeye

Data Acquisition

• Outside CONUS:

– Real-timecollection/downlink toIRS-P6 regional affiliatestation;or stored on OBSSR anddown linked at India.

– Source image generatedat NRSA ProcessingCenter or regionalaffiliate station

– Image delivered toNorman via FTP transfer

IRS-P6 Receiving StationsHyderabad: NRSANeustralitz: EuromapAbu Dhabi: FalconBeijing: RSGS

Data Capturing

• Direct Archival and Quick LookBrowse System (DAQLB)handles simultaneous ingest ofserial bit streams of data fromResourceSat in real-time

• The system also archives thedata on DLT media afterappropriate formatting in FREDformat.

SD

Pro fessio nal Workstati on 6000

PRO

Data Capturing

• The system processes theancillary information andarchives it within a database,that is subsequently used forproduct generation.

• Additionally, this system alsogenerates thumbnail imagesthat can be used in the dataselection process.

SD

Pro fessio nal Workstati on 6000

PRO

Data Processing

• Data Production GenerationSystem (DPGS) consists of aset of processes and runtimefiles containing Satellite andSensor parameters,radiometric look-up tables,configuration files andrelated information requiredfor processing.

SD

Professional Workstation 6000

PRO

Data Processing

• The system downloadsthe raw video datacorresponding to the userarea of interest from theDAQLB system.

• The system thengenerates the sourcedata by executing a set ofprocesses in pre-definedsequence andprecedence.

Data Processing

• Quality control (QC) of source image consists of a visualexamination of the scene. The operator would identifythe following:

– Cloud Cover

– Processing/Downlink anomalies

– Correct path/row/quad/acquisition date

• Customer contacted (email with screen captures) for anyquestionable scenes. All scenes that pass source imageQC are prepared for orthorectification.

Orthorectification

• Most Resourcesat-1 imagerysold to USDA is in the form oforthorectified AWiFS scenes.

• GeoEye has developed aproduction workflow withcustom software to streamlinethe process of datamanagement, control pointmeasurement, blockadjustment andorthorectification

Orthorectification

Major workflow steps:• Ancillary data compilation

- Data staging utility compiles reference orthoimagery andthe DEM

• Control point measurement– Automated image matching software used to collect tie

points– Configured for AWiFS file naming conventions– Matches TIFF + RPC/DEM and reference orthoimage– Operator has the option to redefine the spacing of tie point

measurements. They also have the option to selectmin/max number of points to extract.

• Orthorectification– Imagery optionally scaled from 10 bits per pixel to 8 bits

per pixel– Cubic convolution resampling employed

Final QC

Steps in Quality controlprocess:

• QC operator checksseveral areas withinimage for alignment.

• All areas should be within1 pixel of reference image

• More tie points added andortho regenerated iftolerance is not met

Final QC

• ERDAS IMAGINE ‘swipe’tool used to compareortho with referenceorthoimage

• Ortho viewed withdifferent bandcombinations to ensurethat all 4 bands are OK

• 1 pixel alignment withreference is typicallyachieved with no reworknecessary.

Product Delivery

• 4-band ortho TIFF split into separate bands is generated.

• Final product is transferred to FTP server, wherecustomer can download.

4-band TIFF ortho Output GeoTIFF ortho product

Summary

• Norman Operations continues to provide reliable dataacquisition service of Resourcesat-1

• Custom software used for most data processing steps

• Geoeye’s Resourcesat Orthorectification process isinteractive, but not labor intensive. Providing numerousoperator QC points to ensure the highest productquality.